Time-limit induction relay



June 29 1.926.

l W. H. PETERSN TIME LIMII` INDUCTION RELAY Filed Jan. l1. 1923 Patented June 29, 1926.

:.UN'I T ED ,1S TIEJS .PIENT "LLOFEI d(115;

WILHELM HENNING IPETERSN, `OF.GAMLA -POSTEN,'LU1'JVIKA, SWEDEN, ASSIGNOR TO ALLMANNA SVENSKAELEKTRISKA.'KTIEBOLAGET, VO]?"VASTIER.AS, SWEDENI A CORPORATION OF ,'SWEDEN.

TIMELQMIT INDUCTION RELAY.

.Application led January 11, 1923, Serial No.-611,989,-and1 in ISWeden 'December v'4, .1922.

I,In my pending `patent application No. ...472,848, :I .have described an inverse tiine ylimitrelay otfthe inductiontype, in which `the foperating device (any induction disc orftlierlike) is mountedin a pivoted frame which is balanced in such mannerthat upon a rise of current over a certain value, the H'frame `Will-'be swung `under the iniuence of the induction forces actingupon thedisc or corresponding member so as to br1ng the latter device intoengagement with thereleasing mechanism; of the relay,and thus to -initiate the releasingr Ymovement proper. 1n the said application, it hasbeenpresupposed :that Y:the@tangential force acting from the :electromagnet'to rotate the induction disc :has been the ,force whichanoves vthe frame intooperative position. t

In `f.accordance with -my .present invention, ixI accomplish the desired result Vot moving the induction member into voi'ierative posi- ;tion for Ainitiatingthe releasing movement by `causing the said ,member to be actuated hy an .induction force rdepending upon the `operating current, but acting :1n a ldirection diiferent -from -the tangential one. This lforce fmay for ,an instant consist of .acomrlponent of the same force. of--Which `a tangential vcomponent serves to -rotatelthe 1n- .,duction member (Whichfmayfbe a disc-or a cylinder or lof some intermediary shape). .In ,most cases .it is, however, preferable to derive it rfrom a separate magnetic field, .either yby .providing .a magnetic s hunt to the .driving electromagnet or l.by using a sepa-v rate .c'oil traversed ,by the `same current Yas the electromagnet or by ia current proporxtional thereto. Under'tlie influence oit the seid fforce, the induction member is thus .displaced in a direction diderentirom'the tangential one when moved into its opera- :tive position. Hereby `the advantage is Vgained that the induction member can easily be shaped in such vWay or arrangedin such waywvith respect to the operative flux that the tangential force is increased bythe displacement and again reduced when the memberis displaced in the opposite direc- .operation on-tliis point there is employed,

so to say, a connecting'-anddisconnecting .Oper-tation. between theinduc'tion member and its driving flux.

Initlie drawing. seine forms of" the invenr tion vare.diagrainmatically illustrated. Figure l shows, in a side veW,-.a'relay-having :a common `magnetic field producing: al force upon the induction' memberwvhich is divided into two components, y au tangential driving iorce and a Ydisplacinggforce perpeiidicuklar thereto, andfservlng to ,displace'the in- `duction members. Figure -2 shows, -in a side vieW,a ormin which the displacing force is produced by a separate zmagnetic ifieldiorming a,y magnetic shuntV to thexmain `field. Figure 3 is :a corresponding :'front view, Figure 4 shows a. form; in Whichthe displacing field, which .still forms a magnetic shunt, does Vnot .act directly .on the `induction member, but on .a separate memyber mechanically connected-thereto.

In all the forms shown, the induction `member consists of a disc l moving between Ithe,polesofone electromagnet 2,'tlie coil 3 v.of Whichis traversed by the current serving A:to operate the relay. .member .issupported in a frame@ capable The said induction of rocking about .an ,axis k5, said rocking jmovement being limited pby a .pair of sto s l 6 Xbetweenfwhich moves a portion 7 of tie frame serving-also vas a counterweight.

Thepoles of the magnet 2 exert atangential. driving force on .the induction member -aiidfor this purposefthey are provided, in

a Well-known '.nianner, VWith an auxiliary short-circuited winding which embraces a portion-'oftbe;pole1and produces a flux 1n kWill'foiim a certain yangle With ltlie'tangential direction. iFurther the disc, in its normal ypositiomlias itsedge right in front of the poles, so that the action thereon vfor a certainamount of currentin'the'coil 3 will "be smaller than if the Whole of the pole faces were covered by the disc. By a suitable vcounteracting force, which may'besprovided ,in 4a manner Vfas hereinafterl described, the

kiii'tation of the disc runder 'the influen'eegof `the magnet-.field may be prevented in this y'pnfitiim, .even .1f-the current rises to ythe value for which the relay is intended to operate. @n the other hand, at that current value, the radial component of the force acting on the disc from the field should be sufficient to raise the disc and its suspension device so that the disc Will cover the Whole of the pole surfaces. By the increase in the tangential force hereby gained, it Will be suiiicient to rotate the disc.

The aforesaid counteracting force, Which initially prevents the rotation of the disc, is provided, according to Figure l, by arranging a pinion 9 on the shaft of the disc in permanent engagement With a toothed segment l0, which is mounted on an axis 1l in the trame 4 and has a certainamount of unbalanced Weight, which must be surmounted before the rotation can begin. The toothed segment l0 has a projection 12 Which, after having been raised through a certain distance, acts upon the contacts of the relays or on corresponding' members and performs a releasing action. ln this form the engagement between the driving induction member and the releasing mechanism is thus permanent, but it may also be detachable. The downward movement of the toothed segment l0 is limited by stop 13 on the frame 4C.

The permanent engagement between the tivo main portions oit' the relay has the advantage over the intermittent one suggested in my pending application No. 472,848, that the length of the movement of the releasing mechanism can be more finely adjusted, as it becomes independent 'of the pitch of the engaging members. Hereby also the time setting' oi the relay can be more exact. The creepage is prevented, in spite of the permanent engagement, by the fact that the rotating forces acting upon the induction member are normally considerably reduced. The displacement oi? the induction member into a more ac ive position ivitli respect to the said forces thus corresponds to its bringing into engagement with the releasing mechanism according to my application No. 472,848.

Referring to Figures 2 and 3, the electromagnet has tivo pole pairs, the fluxes of which are parallel to each other. The one pole pair la has a short-circuited coil l5, so arranged as to produce a tangential :torce on the dise l, While the other pole pair 16 with its coil l? pulls the. disc in a radial direction so as to be more strongly influenced by the pole pair 14;. The latter, in analogy with the single pole pair in Figure l, is placed near the edge of the disc, While the pole pair 16 is arranged opposite a weakened portion of: the disc. The weakening, in the torni shown, is accomplished by means of p-erforations 18. Hereby also the induction force is increased as soon as the displace` ment begins. The further details of the form correspond closely to those already described With reference to Figure l.

ln both of the forms described, the magnet can also serve as a braking magnet, since it has either a flux or a` torce component which does not act to rotatethe disc.4

Figure liinallyshows a form in which the magnetic iield serving to pull the induction disc into operative position with respect to the tangential rotating torce, does not act directly on the disc, but on a separate metal piece 19 mounted on frame d supporting the disc. rlhis iield forms a magnetic shunt path 2O oit the driving electromagnet 2. ln this form a separate braking magnet 2l is used, C s the driving iield has no braking component.

l claim as my invention l. ln time relays, a rotatable induction member, a movable frame supporting same, an electromagnet having poles exerting a tangential force on said induction member, and other poles on the same electromagnet producing a :torce for displacing the said induction member.

Q. ln time relays, a. rotatable induction member supported in a movable frame, and an electromagnet having two pairs of poles, one pair arranged to produce a tangential force on said induction member, and the other to produce a force in another direction on said induction member.

3. ln time relays, a rotatable induction member, supported in a. movable frame, and an electromagnet having tvvo` pairs of poles magnetically parallel to each other, one pair off poles arranged to produce a tangential force on said induction member and the .other to produce a force on said member perpendicular to the tangential direction.

Ll. In time relays, a rotatable induction member, an electromagnet having poles eX- erting a tangential force on said member, a vtraine supporting same and displaceable in a. direction perpendicular to said tangential it'orce, and another pair ot poles on the elec tromagnet acting to displace tbe frame in said last-mentioned direction.

5. In time relays, a rotatable induction member, electromagnet poles acting to rotate same, and indepeiident means actuated by other poles for displacing the said induction member *with respect to said poles, so as to bring more et its materia] to be traversed by the iiux of said poles.

6. ln time relays, a rotatable induction member, electromagnet poles acting to rotate same, other electro-magnet poles acting on said member to displace its axis of rotation and to bring more ot its material to be traversed by their proper magnetic flux.

7. In time relays, a rotatable induction member, electromagnct poles acting to rotate same, means for displacing said member with respect to said poles so as to increase the rotating forces acting thereon, a releasing mechanism permanently connected to Said induction member, and means for preventing said member from rotating until said rotating forces have been increased by the displacement.

8. In time relays, a rotatable induction member, electromagnetic means acting to displace said member both in a tangential direction and in a direction perpendicular 10 thereto, the means foi' displacing in said latter direction Serving also to brake the rotating movement of Said induction meinber.

In testimony whereof I have signed my 15 name t0 this specification.

WILHELM HENN ING PETERSN. 

